British police told the Israeli Embassy in London minutes before Thursday's explosions that they had received warnings of possible terror attacks in the city, a senior Israeli official said.

Israeli Finance Minister Benjamin Netanyahu had planned to attend an economic conference in a hotel over the subway stop where one of the blasts occurred, and the warning prompted him to stay in his hotel room instead, government officials said.

Foreign Minister Silvan Shalom said he wasn't aware of any Israeli casualties.

Just before the blasts, Scotland Yard called the security officer at the Israeli Embassy to say they had received warnings of possible attacks, the official said. He did not say whether British police made any link to the economic conference.

The official spoke on condition of anonymity because of the nature of his position.

The Israeli Embassy was in a state of emergency after the explosions in London, with no one allowed to enter or leave, said the Israeli ambassador to London, Zvi Hefet.

All phone lines to the embassy were down, said Danny Biran, an Israeli Foreign Ministry official.

The ministry set up a situation room to deal with hundreds of phone calls from concerned relatives. Thousands of Israelis are living in London or visiting the city at this time, Biran said.

Amir Gilad, a Netanyahu aide, told Israel Radio that Netanyahu's entourage was receiving updates all morning from British security officials, and "we have also asked to change our plans."

Netanyahu had been scheduled to stay in London until Sunday, but that could change, Gilad said.